Epidemiology of Cytomegalovirus Infection After Pancreas Transplantation

Background. Epidemiology of cytomegalovirus (CMV) infection has not been comprehensively studied after all three types of pancreas transplant (PT) including simultaneous pancreas-kidney transplantation (SPK), pancreas transplantation alone (PTA), and pancreas after kidney transplantation (PAK). Methods. We evaluated incidence, risk factors, and outcomes of CMV infection after pancreas transplant at our center from January 1, 1998, to December 31, 2009. Results. The study cohort included 252 recipients (SPK 60, PTA71, and PAK121), 53% men, age 43.9 +/- 9 years, followed for 6.3 (interquartile range 3-9) years. CMV serostatus was donor (D) seropositive and recipient (R) seronegative (D+/R-) (27%), D+/R- (32%), D+/R- (18%), D+/R- (23%), and one unknown/R+ (0.4%). Two hundred six (82%) patients received CMV prophylaxis. Twelve patients experienced CMV viremia, whereas 31 developed CMV disease. The cumulative incidence of CMV infection (viremia and disease) was 15%, 17%, and 20% at 1, 5, and 10 years, respectively, with no events after 10 years. It was higher in D+/R- group (P<0.004) and patients with kidney graft failure (P<0.036). The variables significantly associated with pancreas graft failure were transplant type (PTA vs. SPK, hazard ratio [HR]=2.29, P=0.020; PAK vs. SPK, HR=2.73, P=0.003) and acute pancreas rejection (HR=2.47, P<0.001). In multivariable mortality model, increased age (P<0.001) and pancreas graft failure (P<0.001) were associated with an increased risk of death, whereas CMV infection (P=0.036) was associated with a borderline decreased risk. Conclusions. CMV remains a common cause of clinical illness, particularly among the CMV D+/R- mismatched and patients with kidney graft failure. Marginal association was observed between CMV infection and a lower risk of death, but not with allograft failure.